The gas fire in my home has been used a lot recently and has been forming bubbles of black soot. The coal is burning away and was wondering if this is normal and do they have to be replaced?
NO SOOT SHOULD BE THERE! The arrangement of the coals is normally critical and appears to be stopping complete combustion of the gas. Would advise you stop using immediately and get it checked by a Corgi engineer - check he has HTR1 qualification.
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